Describe two conditions necessary for a chemical reaction to occur

i believe the answer is a or 1

she forgot to record a transaction

this is true, assuming that the allele is completely recessive and incomplete dominance is not a factor.

the menstrual cycle – higher tier. negative feedback mechanisms affect the production of hormones in the menstrual cycle. oestrogen also stimulates the release of lh (luteinising hormone) from the pituitary gland, which in turn controls the production of progesterone.