If 28 - 210 and 212 27, which describes all the lines that must be parallel? S
t
5 6
8/7
12
43
9/10
u
13/14
16/15
12 11
Only lines r and s must be parallel.
o Only lines t and u must be parallel.
O Lines r and s and lines tand u must be parallel.
ONeither lines r and s nor lines t and u must be parallel.

Aclassroom is made up of 11 boys and 14 girls. the teacher has four main classroom responsibilities that she wants to hand out to four different students (one for each of the four students). if the teacher chooses 4 of the students at random, then what is the probability that the four students chosen to complete the responsibilities will be all boys?