The two-way table shows the number of students in a middle school who have 0, 1, 2, or 3 siblings.

Siblings Grade 7 Grade 8 Total
0 10 7 17
1 15 14 29
2 8 18 26
3 7 6 13
Total 40 45 85
How many more 7th graders than 8th graders have 1 or no siblings?

A. 90 degrees b. 45 degrees c. 30 degrees d. 120 degrees

The function v(r)=4/3pir^3 can be used to find the volume of air inside a basketball given its radius. what does v(r) represent

Aroulette wheel has 38 slots in which the ball can land. two of the slots are green, 18 are red, and 18 are black. the ball is equally likely to land in any slot. the roulette wheel is going to be spun twice, and the outcomes of the two spins are independent.the probability that it lands one time on red and another time on black in any order is(a) 0.5 (b) 0.25 (c) 0.4488 (d) 0.2244