I believe it’s A. I know for sure it isn’t D.
Answer:
40 cm
Explanation:
The focus of a spherical convex mirror is the point at which the rays of an object converge in the infinite, it is also the point at which an object must be placed so that its image is formed in the infinite. The distance from the focus to the origin is called the focal length and is called f. It is related to the radius of the mirror, R, according to:

rewriting for R:
.
Answer:im so sorry i cant find anything either ask your teacher for some help is the best thing i can do
Answer:
-2.5 is the answer to your question
Answer:
9ms^2
Explanation:
since ,Force=mass*acceleration
then, acceleration=force/mass
and, Force=90N
Mass=10pound
therefore, acceleration=90/10
=9ms^2