The tough superficial layer of the epidermis is known as the stratum a) corneum. b) lucidum. c) basale. d) granulosum. e) spinosum.

Stratum corneum

Explanation:

Epidermis is known to be the outmost layer of the skin and it is made up of stratified squamous epithelium and keratinized.  Thus, stratum corneum is known to be the layer of the epidermis that is most superficial and that can be seen with our eyes. Furthermore, stratum corneum functions by preventing the dehydration of underlying tissues and microbes penetration

correct answer is option a.

tropopause, stratopause and mesopause have all in common aspect that is point of maximum temperature in its layer of the atmosphere. all layers of atmosphere observe abrupt change in temperature. tropopause is the boundary between troposphere and stratosphere. stratopause is the boundary between stratosphere and mesosphere. mesopause is the boundary between mesosphere and thermosphere. these all boundaries are ranges between altitude of 0 to 80 km.