Evaluate 4.7 j - 6.8 k when j equals 5 + k equals 3

Steve wants to develop a way to find the total cost of any item including sales tax. the sales tax in his city is 6%. his friend jenna writes the expression x + 6x where x is the cost of the item. explain whether her expression is correct based on the situation.

[10 points, algebra 2]according to my answer key the restrictions are -1 and 4. but why not positive 1?

The weights of broilers (commercially raised chickens) are approximately normally distributed with mean 1387 grams and standard deviation 161 grams. what is the probability that a randomly selected broiler weighs more than 1,425 grams?