how could you reword these research hypoteses to null hypoteses?
a) smoking during pregnancy increse the risk of a child being born orematurely.
b) regular exercise in older adults decreases blood pressure levels.
To reword these research hypotheses into null hypotheses, we need to state them in a way that assumes there is no relationship or effect being investigated. Here's how they could be rephrased:
a) The null hypothesis would state that there is no difference in the risk of a child being born prematurely between pregnant women who smoke and those who do not smoke.
b) The null hypothesis would state that there is no difference in blood pressure levels between older adults who engage in regular exercise and those who do not exercise regularly.
Essentially, the null hypothesis assumes that there is no true effect or relationship between the variables being studied.