Here are the sources for the pictures I used in this website:
http://www.google.com/imgres?um=1&hl=en&tbo=d&authuser=0&biw=1366&bih=673&tbm=isch&tbnid=HzoBMLOC0c59RM:&imgrefurl=http://en.wikipedia.org/wiki/File:Ski_trail_rating_symbol-blue_square.svg&docid=ZvP1zjfFQwLm-M&imgurl=http://upload.wikimedia.org/wikipedia/commons/thumb/0/0d/Ski_trail_rating_symbol-blue_square.svg/600px-Ski_trail_rating_symbol-blue_square.svg.png&w=600&h=600&ei=8zSkUISDDo3PqAGF2oGwDg&zoom=1&iact=hc&vpx=510&vpy=318&dur=860&hovh=225&hovw=225&tx=96&ty=138&sig=115299990634837735249&page=1&tbnh=143&tbnw=142&&ndsp=26&ved=1t:429,r:12,s:0,i:186
http://www.google.com/imgres?um=1&hl=en&tbo=d&authuser=0&biw=1366&bih=673&tbm=isch&tbnid=BJrMwTScgMZ9AM:&imgrefurl=http://scienceforkids.kidipede.com/math/geometry/rectangle.htm&docid=36905iYXvVcxCM&imgurl=http://scienceforkids.kidipede.com/math/geometry/pictures/rectangle.gif&w=355&h=180&ei=JjakUN6VLY-qqAGkm4CYAw&zoom=1&iact=hc&vpx=1039&vpy=370&dur=536&hovh=144&hovw=284&tx=137&ty=72&sig=115299990634837735249&page=1&tbnh=125&tbnw=224&&ndsp=20&ved=1t:429,r:13,s:0,i:176
http://www.google.com/imgres?um=1&hl=en&tbo=d&authuser=0&biw=1366&bih=673&tbm=isch&tbnid=kuMC2yk4y3FzcM:&imgrefurl=http://en.wikipedia.org/wiki/File:Green_equilateral_triangle_point_up.svg&docid=2Icd3fUSpzmWcM&imgurl=http://upload.wikimedia.org/wikipedia/commons/thumb/7/7f/Green_equilateral_triangle_point_up.svg/600px-Green_equilateral_triangle_point_up.svg.png&w=600&h=520&ei=rTakUI-RJIjwrQG3m4CQBQ&zoom=1
http://www.google.com/imgres?um=1&hl=en&tbo=d&authuser=0&biw=1366&bih=673&tbm=isch&tbnid=2fmdX0OoM581kM:&imgrefurl=http://iphone.netarbeiter.com/shapes/&docid=j0Y97qZBDUkYoM&imgurl=http://iphone.netarbeiter.com/shapes/png/trapezoid_purple.png&w=440&h=220&ei=YzekUMnIEs7kqAGW0IGICw&zoom=1&iact=hc&vpx=898&vpy=355&dur=2351&hovh=159&hovw=318&tx=153&ty=82&sig=115299990634837735249&page=1&tbnh=143&tbnw=286&&ndsp=18&ved=1t:429,r:10,s:0,i:167
http://www.google.com/imgres?hl=en&tbo=d&authuser=0&biw=1366&bih=673&tbm=isch&tbnid=NHJPPag_WbOLwM:&imgrefurl=http://www.k6-geometric-shapes.com/geometry-shapes.html&docid=-Vp__NR5asw5EM&imgurl=http://www.k6-geometric-shapes.com/image-files/2d-complex-shaoe.jpg&w=192&h=192&ei=cTikUNfHHsi7qQHmgoHQDQ&zoom=1&iact=hc&vpx=716&vpy=207&dur=1046&hovh=153&hovw=153&tx=95&ty=97&sig=115299990634837735249&page=1&tbnh=140&tbnw=121&&ndsp=23&ved=1t:429,r:4,s:0,i:123
http://www.google.com/imgres?hl=en&sa=X&tbo=d&biw=1366&bih=673&tbm=isch&tbnid=-GvkL9d5lhdcKM:&imgrefurl=http://misstowermath.weebly.com/measurement1.html&docid=7swzG8b1vwylLM&imgurl=http://misstowermath.weebly.com/uploads/3/7/3/1/3731108/1723028.jpg%253F373&w=373&h=241&ei=ejmkUK_vINL2rAGK8oCoCQ&zoom=1&iact=hc&vpx=2&vpy=148&dur=7609&hovh=180&hovw=279&tx=100&ty=71&sig=115299990634837735249&page=1&tbnh=118&tbnw=172&&ndsp=22&ved=1t:429,r:0,s:0,i:74
http://www.google.com/imgres?hl=en&sa=X&tbo=d&biw=1366&bih=673&tbm=isch&tbnid=0ljiYKNS2LNK2M:&imgrefurl=http://mrnussbaum.com/grade_3_standardsareafigures/&docid=0n66OERXQOJt8M&imgurl=http://mrnussbaum.com/mathdrills/grade3standards/complex1.gif&w=425&h=400&ei=ejmkUK_vINL2rAGK8oCoCQ&zoom=1&iact=hc&vpx=2&vpy=278&dur=269&hovh=218&hovw=231&tx=82&ty=132&sig=115299990634837735249&page=1&tbnh=151&tbnw=161&&ndsp=22&ved=1t:429,r:7,s:0,i:95
http://www.google.com/imgres?hl=en&sa=X&tbo=d&biw=1366&bih=673&tbm=isch&tbnid=NhG0g0kZv1911M:&imgrefurl=http://mrnussbaum.com/grade_3_standardsareafigures/&docid=0n66OERXQOJt8M&imgurl=http://mrnussbaum.com/mathdrills/grade3standards/complex3.gif&w=440&h=400&ei=ejmkUK_vINL2rAGK8oCoCQ&zoom=1&iact=hc&vpx=484&vpy=280&dur=622&hovh=214&hovw=235&tx=129&ty=100&sig=115299990634837735249&page=1&tbnh=151&tbnw=166&&ndsp=22&ved=1t:429,r:10,s:0,i:104
http://www.google.com/imgres?num=10&hl=en&tbo=d&authuser=0&biw=1366&bih=673&tbm=isch&tbnid=cHGGW7hfQSQOUM:&imgrefurl=http://www.mathsteacher.com.au/year9/ch14_measurement/11_comp/fig.htm&docid=mZLxzz5AaW0-cM&imgurl=http://www.mathsteacher.com.au/year9/ch14_measurement/11_comp/Image15581.gif&w=306&h=139&ei=yT2kUM7jB4yW8gTEt4DQCg&zoom=1&iact=hc&vpx=1079&vpy=341&dur=800&hovh=111&hovw=244&tx=56&ty=60&sig=115299990634837735249&page=1&tbnh=110&tbnw=241&&ndsp=20&ved=1t:429,r:12,s:0,i:110
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http://www.google.com/imgres?hl=en&tbo=d&biw=1366&bih=673&tbm=isch&tbnid=Qrr18y1KQu3Z7M:&imgrefurl=http://www.k6-geometric-shapes.com/complex-shapes.html&docid=kJ9S3m--LsyCMM&imgurl=http://www.k6-geometric-shapes.com/image-files/2d-complex-shape.jpg&w=480&h=480&ei=Bla1UN6PFImMqwHE6IGADQ&zoom=1&iact=rc&dur=110&sig=115299990634837735249&page=1&tbnh=143&tbnw=145&&ndsp=20&ved=1t:429,r:12,s:0,i:120&tx=97&ty=56
http://www.google.com/imgres?um=1&hl=en&tbo=d&authuser=0&biw=1366&bih=673&tbm=isch&tbnid=HzoBMLOC0c59RM:&imgrefurl=http://en.wikipedia.org/wiki/File:Ski_trail_rating_symbol-blue_square.svg&docid=ZvP1zjfFQwLm-M&imgurl=http://upload.wikimedia.org/wikipedia/commons/thumb/0/0d/Ski_trail_rating_symbol-blue_square.svg/600px-Ski_trail_rating_symbol-blue_square.svg.png&w=600&h=600&ei=8zSkUISDDo3PqAGF2oGwDg&zoom=1&iact=hc&vpx=510&vpy=318&dur=860&hovh=225&hovw=225&tx=96&ty=138&sig=115299990634837735249&page=1&tbnh=143&tbnw=142&&ndsp=26&ved=1t:429,r:12,s:0,i:186
http://www.google.com/imgres?um=1&hl=en&tbo=d&authuser=0&biw=1366&bih=673&tbm=isch&tbnid=BJrMwTScgMZ9AM:&imgrefurl=http://scienceforkids.kidipede.com/math/geometry/rectangle.htm&docid=36905iYXvVcxCM&imgurl=http://scienceforkids.kidipede.com/math/geometry/pictures/rectangle.gif&w=355&h=180&ei=JjakUN6VLY-qqAGkm4CYAw&zoom=1&iact=hc&vpx=1039&vpy=370&dur=536&hovh=144&hovw=284&tx=137&ty=72&sig=115299990634837735249&page=1&tbnh=125&tbnw=224&&ndsp=20&ved=1t:429,r:13,s:0,i:176
http://www.google.com/imgres?um=1&hl=en&tbo=d&authuser=0&biw=1366&bih=673&tbm=isch&tbnid=kuMC2yk4y3FzcM:&imgrefurl=http://en.wikipedia.org/wiki/File:Green_equilateral_triangle_point_up.svg&docid=2Icd3fUSpzmWcM&imgurl=http://upload.wikimedia.org/wikipedia/commons/thumb/7/7f/Green_equilateral_triangle_point_up.svg/600px-Green_equilateral_triangle_point_up.svg.png&w=600&h=520&ei=rTakUI-RJIjwrQG3m4CQBQ&zoom=1
http://www.google.com/imgres?um=1&hl=en&tbo=d&authuser=0&biw=1366&bih=673&tbm=isch&tbnid=2fmdX0OoM581kM:&imgrefurl=http://iphone.netarbeiter.com/shapes/&docid=j0Y97qZBDUkYoM&imgurl=http://iphone.netarbeiter.com/shapes/png/trapezoid_purple.png&w=440&h=220&ei=YzekUMnIEs7kqAGW0IGICw&zoom=1&iact=hc&vpx=898&vpy=355&dur=2351&hovh=159&hovw=318&tx=153&ty=82&sig=115299990634837735249&page=1&tbnh=143&tbnw=286&&ndsp=18&ved=1t:429,r:10,s:0,i:167
http://www.google.com/imgres?hl=en&tbo=d&authuser=0&biw=1366&bih=673&tbm=isch&tbnid=NHJPPag_WbOLwM:&imgrefurl=http://www.k6-geometric-shapes.com/geometry-shapes.html&docid=-Vp__NR5asw5EM&imgurl=http://www.k6-geometric-shapes.com/image-files/2d-complex-shaoe.jpg&w=192&h=192&ei=cTikUNfHHsi7qQHmgoHQDQ&zoom=1&iact=hc&vpx=716&vpy=207&dur=1046&hovh=153&hovw=153&tx=95&ty=97&sig=115299990634837735249&page=1&tbnh=140&tbnw=121&&ndsp=23&ved=1t:429,r:4,s:0,i:123
http://www.google.com/imgres?hl=en&sa=X&tbo=d&biw=1366&bih=673&tbm=isch&tbnid=-GvkL9d5lhdcKM:&imgrefurl=http://misstowermath.weebly.com/measurement1.html&docid=7swzG8b1vwylLM&imgurl=http://misstowermath.weebly.com/uploads/3/7/3/1/3731108/1723028.jpg%253F373&w=373&h=241&ei=ejmkUK_vINL2rAGK8oCoCQ&zoom=1&iact=hc&vpx=2&vpy=148&dur=7609&hovh=180&hovw=279&tx=100&ty=71&sig=115299990634837735249&page=1&tbnh=118&tbnw=172&&ndsp=22&ved=1t:429,r:0,s:0,i:74
http://www.google.com/imgres?hl=en&sa=X&tbo=d&biw=1366&bih=673&tbm=isch&tbnid=0ljiYKNS2LNK2M:&imgrefurl=http://mrnussbaum.com/grade_3_standardsareafigures/&docid=0n66OERXQOJt8M&imgurl=http://mrnussbaum.com/mathdrills/grade3standards/complex1.gif&w=425&h=400&ei=ejmkUK_vINL2rAGK8oCoCQ&zoom=1&iact=hc&vpx=2&vpy=278&dur=269&hovh=218&hovw=231&tx=82&ty=132&sig=115299990634837735249&page=1&tbnh=151&tbnw=161&&ndsp=22&ved=1t:429,r:7,s:0,i:95
http://www.google.com/imgres?hl=en&sa=X&tbo=d&biw=1366&bih=673&tbm=isch&tbnid=NhG0g0kZv1911M:&imgrefurl=http://mrnussbaum.com/grade_3_standardsareafigures/&docid=0n66OERXQOJt8M&imgurl=http://mrnussbaum.com/mathdrills/grade3standards/complex3.gif&w=440&h=400&ei=ejmkUK_vINL2rAGK8oCoCQ&zoom=1&iact=hc&vpx=484&vpy=280&dur=622&hovh=214&hovw=235&tx=129&ty=100&sig=115299990634837735249&page=1&tbnh=151&tbnw=166&&ndsp=22&ved=1t:429,r:10,s:0,i:104
http://www.google.com/imgres?num=10&hl=en&tbo=d&authuser=0&biw=1366&bih=673&tbm=isch&tbnid=cHGGW7hfQSQOUM:&imgrefurl=http://www.mathsteacher.com.au/year9/ch14_measurement/11_comp/fig.htm&docid=mZLxzz5AaW0-cM&imgurl=http://www.mathsteacher.com.au/year9/ch14_measurement/11_comp/Image15581.gif&w=306&h=139&ei=yT2kUM7jB4yW8gTEt4DQCg&zoom=1&iact=hc&vpx=1079&vpy=341&dur=800&hovh=111&hovw=244&tx=56&ty=60&sig=115299990634837735249&page=1&tbnh=110&tbnw=241&&ndsp=20&ved=1t:429,r:12,s:0,i:110
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http://www.google.com/imgres?hl=en&tbo=d&biw=1366&bih=673&tbm=isch&tbnid=Qrr18y1KQu3Z7M:&imgrefurl=http://www.k6-geometric-shapes.com/complex-shapes.html&docid=kJ9S3m--LsyCMM&imgurl=http://www.k6-geometric-shapes.com/image-files/2d-complex-shape.jpg&w=480&h=480&ei=Bla1UN6PFImMqwHE6IGADQ&zoom=1&iact=rc&dur=110&sig=115299990634837735249&page=1&tbnh=143&tbnw=145&&ndsp=20&ved=1t:429,r:12,s:0,i:120&tx=97&ty=56