Answer: B. a moving cold air mass
A warm front is defined as the transition zone where a cold air mass is replaced by a warm air mass. Warm fronts generally move from southwest to northeast (not rising, but moving nor trapped) and the air behind a warm front is warmer and more moist than the air ahead of it.
Dogs because cell differentiation is the same as cell specialization and also daisies
Changing only one variable at a time is a rule for conducting a controlled
experiment.
Controlled experiment involves the use of dependent and independent
variables . Changes in the independent variable brings about a
corresponding change in the dependent variable which is then recorded.
It is however important to note that changing more than only one variable at
a time won't accurately determine if the changes in the results were as a
result of one cause. This is why only one variable has to be changed at a
time.
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