Angles 1 and 2 are adjacent, we know this because they are side by side. Meaning they are adjacent.
Angles 1 and 2 are also complementary because they add up to 90°
There's only information to answer question C.
We can only know that 32 marbles were chosen. (yellow and black)
Why?
To answer the first two questions (a and b), we need to know the total number of marbles, so, we can only answer the last question (c).
We know that 7/10 of the 20 yellow marbles were chosen.
So, calculating we have:

Also, we know that 18 black marbles were chosen, so, the total of marbles chosen is equal to 32 (yellow marbles and black marbles)

Have a nice day!
4/x-1 would be the equation written from that statement.
2÷5=0.4
1÷4=0.25
0.4÷0.25=0.016
so she walks at a rate of 0.016 miles per hour