Can somoene explain to me how punnett squares work

Scientific method and data analysisa biology student wanted to determine if there is a relationship between resting heart rate and bodyheight. she gathered information from 12 classmates and constructed the table below.resting heart rate (beats per minute)student height (cm)155. 156156165180180190194195

What element is able to combine with itself and hydrogen to form large molecules ?

What makes a dominant allele different from a recessive allele