Every bit can either be a 0 or 1. So to find the amount of bit strings of length either, you do 2length to find the amount of bit strings there are of a given length.
1024
Half of them.
1024 of them.
To find the number of strings of length less than 4 that match the regular expression ((x y)y(a , | , ab)), we first analyze the components. The expression can generate strings of length 3: "xyy", "xyab", and also strings of length 2: "xyy" (from the first part) and "xy" (if we consider the empty string for the last part). Therefore, the valid strings of length less than 4 are "xyy", "xyab", and the empty string, leading to a total of 3 valid strings.
its 2 raised to power 8 i.e 256
You are essentially asking how many different bit strings of length 9 are there, as the first 3 bits are fixed. The answer is 2^9 = 512.
Since there are 8 bits in between, and they can assume any of the two values (0 or 1), that results in a total of 28 different combinations.
-- There are 256 bit strings of length 8 . -- There are 4 bit strings of length 2, and you've restricted 2 of the 8 bits to 1 of those 4 . -- So you've restricted the whole byte to 1/4 of its possible values = 64 of them.
Every bit can either be a 0 or 1. So to find the amount of bit strings of length either, you do 2length to find the amount of bit strings there are of a given length.
1024
210=1024
Half of them.
A parachute needs four strings. However, redundancy is best, both for safety and control of the chute. Thus, 16 striings is better, 32 even moreso. Washers around groups of strings cuts down on the likelihood of entanglement. The length of the strings matters, as well (and so does the diameter of the parachute).
There are no zero-length strings that start with 1 bit or end with 2 bits. In a zero-length string, there are no bits at all.
Five (5) have one or the other but not both. Six (6) have both. Total of eleven (11).
1024 of them.