Answer quickly, is urgent

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The multiplication property of zero states that the product of any number and 0 is 0. what must be true about either a or b to make ab=0

Find the directions in which the function increases and decreases most rapidly at upper p 0p0. then find the derivatives of the function in these directions. f(x,y)equals=x squared plus xy plus y squaredx2+xy+y2, upper p 0p0left parenthesis 1 comma negative 4 right parenthesis

Paul can type 60 words per minute and jennifer can type 80 words per minutes.how does paul's typing speed compare to jennifer's