Can someone be nice and help me understand because I really dont

Which of the following is correct interpretation of the expression -4+13

The probability that an adult possesses a credit card is .70. a researcher selects two adults at random. by assuming the independence, the probability that the first adult possesses a credit card and the second adult does not possess a credit card is:

The ph level of a blueberry is 3.1 what is the hydrogen-ion concentration [h+] for the blueberry