Rafael writes an expression to represent “a number, n, decreased by thirty-one.” Then he evaluates that expression if n = 29. Which statements are true about the expression and its evaluation? Check all that apply. The correct expression is 31 minus n.
This is a subtraction expression.
This is an addition expression.
To evaluate, substitute 29 for the variable in the expression.
To evaluate, substitute 31 for the variable in the equation.
To evaluate the expression, add 31 to 29.
The correct expression is n minus 31.
To evaluate the expression, subtract 31 from 29.

Along with the kidneys, the ureters, bladder, and urethra make up the urinary system. match each function or description to the appropriate structure.

New york city has 2,181 inhabitants per square mile. the state of alaska has 1.03 inhabitants per square mile. ecologists would say alaska has a low exponential growth population density birth rate carrying capacity

Darrel conducted an experiment with the following procedure: fill two cups with ice water. place an uninflated balloon snuggly onto your left index finger. blow a little air into an identical balloon, and place it onto your right index finger. place both fingers into the cups of ice water. darrel noticed that his right finger felt warmer in the ice water than did his left finger. which of the following does the experiment show? a. air is a good radiator of heat. b. air is a good insulator of heat. c. air is a good conductor of heat. d. air is a good convector of heat.