Pls help me 1:__Cu20 + ___C ↠__Cu + ___CO2

2:___ Na + ___O2 ↠ ___ Na2O
3:___ C2H4 + ___ O2 → ___ CO2 + ___ H2O
4:___ C4H10O + ___ O2 ↠ ___ CO2 + ___ H2O

genetic variation can be caused by mutation (which can create entirely new alleles in a population), random mating, random fertilization, and recombination between homologous chromosomes during meiosis (which reshuffles alleles within an organism's offspring).

the correct answer in apex is tissue development, i know because i just had this question

can you make it bigger i can't see it