please help me do the three Q thank you i will really appreciate it

Answer:
9.9 or 10
Step-by-step explanation:
With a right triangle you can use the formula a^2+b^2=c^2
c is the missing side
7^2+7^2=c^2
49+49=c^2
98=c^2
9.899=c^2
Either round this to 9.9 or 10