When a substance freezes, what happens to the mass?
a. the mass stays constant as it changes from a liquid to a solid.
b. the mass increases as it changes from a liquid to a solid.
c. the mass decreases as it changes from a liquid to a solid.
d. there is no mass once the substance becomes a solid.

answer: national resource conservation services

national resource conservation services is the us. based approach that provides technical and financial assistance for natural resource management. nrcs society in conservation of resources by involving in activities like farmland protection, flood prevention, watershed protection, urban conservation, conserves economic and environmental conditions. it conducts soil surveys and implements the policy of natural resources management on the society.

both male and female gametes are produced by meiosis of the germ cells. therefore, both male and female gametes are haploid. one male and one female gamete unite during the fertilization to form the diploid zygote. in seed bearing plants, pollen grain is the male gametophyte, which produces sperm cells.