I think it’s either a or d
I would either use a histogram or a frequency chart, but histogram is easier and neater
3days=3chapters so he would have to read for 8 days
You literally need to apply the formula

where
is the mass and
is the speed
Number 1: To find number 1 use hypotenuse theory. 180-(69+31) is the equation. After you solve it you get m<1 as 80.
Number 2: Since you already found m<1 find the other angle across from it.
Equation is: 180-80, which equals to 100.
Then once you have two angles use the theory again: 180-(100+45)=35.
Therefore m<2=35.
Number 3: Still using m<1, 180-100=80. Now you have to angles you get the equation:
180-(80+47), which equals to 53. Therefore m<3=53
Answers: m<1=80; m<2=35; m<3=53