Which of the following describes the way substances diffuse in and out of a cell? A. Substances move from lesser to greater concentration.

B. Substances move back and forth across the membrane equally.

C. Substances move across the membrane when energy is available.

D. Substances move from greater to lesser concentration.

Answer please it would help me alot and thx

What is the approximate total length of iron edging needed to create the square frame and the two diagonals?

You eat $0.85 for every cup of hot chocolate you sell. how many cups do you need to sell to earn $55.25

A. the following events are mutually exclusive: living in california and watching american idol. true or false b. the number of patients seen by an outpatient practice is an example of a discrete random variable. true or false c.the law of large numbers states that as the number of times an event experiment is conducted increases, the likelihood of the actual probability of an event approaching the theoretical probability decreases. true or false d. measuring the time it takes for patients to enter the operating room is an example of a continuous random variable. true or false