Express the following ratio in its lowest terms:
$1\frac{1}{4}:1\frac{2}{3}$

Twenty students in an introductory psychology class were selected by random sampling and asked to participate in an experiment to determine the effects of sunlight on sleeping patterns.What is the experimental unit/subject?

A) The 20 students
B) The entire psychology class
C) The sunlight
D) Different sleeping patterns

When variables change in the same direction,what type of correlation is this called?

A) positive correlation
B) negative correlation
C) positive causation
D) negative causation

A stock valued at $150 increased by 25% and then decreased by 25%. What was the value of the stock after the decrease?

A) $140.63
B) $150.00
C) $187.50
D) $112.50
E) $125.00

Toby's Tiny Toys have an expense equation of E = 12.45q + 53,900.Toby's sell its toys for $16.50 each,and its revenue equation is R = 16.5q.How many tiny toys does it have to sell to reach its breakeven point?