Jean is planning to take a foreign-language class. to research how satisfied other students are with their foreign language classes, she decides to take a sample of 50 such students. the university offers classes in five languages: spanish, german, russian, french, and japanese. she will select a random sample of 10 students from each language. what best describes the sampling technique jean is using?
a) a simple random sample
b) a stratified random sample
c) a voluntary response sample

b) a stratified random sample

Step-by-step explanation:

Stratified random sampling is a sampling process that includes dividing a group into smaller  groups called strata.

The strata are established in stratified random sampling or stratification  on the basis of mutual characteristics or features of participants.

answer: c, the green line

step-by-step explanation:

there is no black line, eliminate b.

simple interest implies periodic payments, but the red line shows no payments, eliminate d.

simple interest has equal payments. if paid say every day, the graph is about a straight line (actually a stairstep).

the yellow line is not straight, eliminate a.

check: the green line is straight, answer is c.

simple interest with positive interest rate gives a straight line sloping up to the right. green line:

g(t) = $100 + ($200-$100) ÷ (20 years) × (t years)

= $100 + (4%/year) × ($100)(t years)

incidentally, the yellow line curving upward represents continuously compounded interest

y = $100 × 2^(t years / (14 assuming the yellow line hits $200 at 14 years. 2^0 is 1, so y(0) = $100; 2^(14/14) is 2, so y(14) = $200.