prior to the industrial revolution, what was the previous highest level of co2 concentration in the atmosphere over the prior 400,000 years?

In my email i got a message it says a quick message and in message details on who its from its says nicole and under nicole is [email protected] -

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?

Q-1 which of the following can exist as cloud-based it resources? a. physical serverb. virtual serverc. software programd. network device