Sonia wants to examine the impact of phone calls versus texting on friendship quality. She carefully designs her study to establish all three causal criteria. She randomly assigns participants to either only call their best friend for 2 days or only text their best friend for 2 days. Using random assignment ensures that the participants in the phone call and texting conditions are not systematically different, which establishes

the number of possible outcomes that do not show a 1 on the first spinner and show the number 4 on the second spinner is 2.

spinner 1 spinner 2

1                     1

1                     2

1                     3

1                     4

2                   1

2                   2

2                   3

2                   4   = not 1, and 4

3                   1

3                   2

3                   3

3                   4 = not 1, and 4

only 2 outcomes have passed the given condition.

step-by-step explanation:

part a: 1.08

part b: 27.59

3

step-by-step explanation: