Studying a group of children from first grade through high school to see the effect of pre-schooling on educational success would be which type of study?
a
longitudinal
cross-sectional
Ос
natural observation
Od
experimental

Use the frequency distribution, which shows the number of american voters (in millions) according to age, to find the probability that a voter chosen at random is in the 18 to 20 years old age range. ages frequency 18 to 20 5.9 21 to 24 7.7 25 to 34 20.4 35 to 44 25.1 45 to 64 54.4 65 and over 27.7 the probability that a voter chosen at random is in the 18 to 20 years old age range is nothing. (round to three decimal places as needed.)

Ineed to know the ordered pairs for this equation i need the answer quick because it’s a timed test

At your job you're paid $50 per week plus $3 per sale at least how many saled do you need to make in order to have over $250