Question 1176628
You have the formula and enough given values; so just substitute and evaluate what is asked.   (and maybe you need to do one small simple unit conversion.)
(In fact you could do this one in your head - no need to write anything.)



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You already know d=rt.
You are GIVEN r, 12 MILES PER HOUR and t, {{{1/2}}}{{{HOUR}}}.
SUBSTITUTE AND EVALUATE!