Children should use a booster seat until they are at least

The measure of the behavior of the subjects in a controlled experiment is called the

(a) dependent variable (b) control variable (c) random variable (d) independent variable

While eating lunch in her highchair, Darci, a six-month-old baby, accidentally drops her spoon. After dropping her spoon, Darci is likely to ___

a. appear unaffected b. look in her hand for the spoon c. look on the floor for the spoon, but give up looking if the spoon is not partially visible d. scan and search the floor persistently for the spoon until she finds it