In humans, being a tongue roller (R) is dominant over non-roller (r). If both parents are heterozygous for tongue rolling. What is the probability of producing a heterozygous tongue roller child?

50%

Explanation:

This is because the Father will have Rr and the mother RR that being said if you do a chart you will find out it is 50%

R   RR   RR

r    Rr    Rr

condenser is used to focus in the light microscope.

the sun creates it's own light, also gives light and life to bunch of stuff like plants,animals,humans etc.photosyntesis is the process of making food which needs sun,water,nutrients etc.