According to the Doppler effect, the sound of a police car siren is louder and high pitched as it approaches the observer.
The head at the top, the tail is just for getting to the egg
In making an experiment their are two types of variable that should be consider, one is the dependent variable and the other one is the independent variables. I the question that dependent variable would be the result or the effect of the gender of mice and the independent is the ways in determining it. So the variables should be fair if you want your result to have no bias. Thus the answer would be letter B. because it has the same variables but different in gender
Helper T cells become activated by interacting with antigen presenting cells. and the second blank space is either cytotoxic t cells or B cells
