What is o.91 written in scientific notation

The general form of the quetion of a circle is ax^2+by^2+cx+dy+e=0 where a=b=0 if the circle has a radius of three units and the center lies on the y axis which set of values of a, b, c, d, and e might correspond to the circle

Can someone me do math because i am having a breakdown rn because i don’t get it

Given ab and cb are tangents of p, and m =10°. what is the measure of abp?