Find the area of the circle

Super ultra mega important if you can answer this correctly i will give you 100 points but if you don't answer it correctly you'll get a big report. so stay aware and have a nice day!

Find the pattern and use it to list the nth term in the sequence. 6, 12, 20, 30, 42, 56, the nth term of the sequence is

Astick 2 m long is placed vertically at point b. the top of the stick is in line with the top of a tree as seen from point a, which is 3 m from the stick and 30 m from the tree. how tall is the tree?