Skim coating weak concrete is only a temporary fix. Another option is to lay a thicker overlay and slow-dry the new surface. To slow-dry, cover the driveway with moist, breathable material. Keep the material wet to provide additional moisture for the concrete to absorb.
The two main sources of genetic variation are gene shuffling and  mutations. A mutation is a process wherein the structure of a gene  is altered.Edit. Share to: Blobbert. 37,033 Contributions. Answered.In Genetic Engineering.he 4 types of genetic variation are 1) mutation-is the mutation of a gene. this is really rare, most mutations are in the recessive trait so they are hidden by a dominant t â¦ rait. Most mutations have no effect but some can be harmful and very few have positive effects.
  In meiosis, one source of genetic variation is crossing-over, which is the exchange of corresponding segments of DNA between non-sister chromatids, in other words chroma â¦ tids of two different homologous chromosomes.This process recombines segments of maternal and paternal DNA along the molecule.here are three sources of genetic variation in meiosis: 1) Independent assortment = like shuffling a deck of cards and dealing out half the deck. 2) Crossing over = homologous chromosomes swap parts, making new combinations.