How do you know if a remote host is alive or not?

The three logical operators used to write compound conditions are "and," "or," and "not." a: true b: false

Martha is a healer, a healthcare provider, and an experienced nurse. she wants to share her daily experiences, as well as her 12 years of work knowledge, with people who may be interested in health and healing. which mode of internet communication can martha use?

Acomputer has a two-level cache. suppose that 60% of the memory references hit on the first level cache, 35% hit on the second level, and 5% miss. the access times are 5 nsec, 15 nsec, and 60 nsec, respectively, where the times for the level 2 cache and memory start counting at the moment it is known that they are needed (e.g., a level 2 cache access does not even start until the level 1 cache miss occurs). what is the average access time?