How many bit strings of length seven either begin with two 0s or end with three 1s?

The purpose of this question is to find the number of bit-strings of length $7$ beginning with two $0$s and ending with three $1$s.The sequence of binary digits is usually called a bit-string. The number of bits signifies the value length in the sequence. A bit-string having no length is regarded as a null string. Bit-strings are useful for representing sets and manipulating binary data. The bit-string elements are labeled left to right from $0$ to one minus the total number of bits in the string. When converting a bit string to an integer, the $0^{th}$ bit corresponds to the $0^{th}$ exponent of two, the first bit corresponds to the first exponent, and so forth.In discrete mathematics, the subsets are represented by the bit-strings in which $1$ indicates that a subset contains an element of a respective set and $0$ indicates that the subset does not contain that element. The representation of a set by a bit-string makes it simple to take complements, intersections, unions, and set differences.