Plants have what is called an blank life cycle

Haploid and diploid life cycle. Haploid male and female cells form together to create a diploid zygote, however when spores or seeds are released (depending on the type of plant) these are once again haploid cells - hence the cycling between cell states

the answer is; comparing the frequency of collisions with and without the device

this makes the anti-collision system an independent variable and the collisions a dependent variable. if there are fewer collisions with an anti-collision system that without, then it can be stated that the system is a success. essentially, collisions under an anti-collision system are compared with the frequency of collisions by cars with the human drivers.