\( 1< \) Students stuff envelopes for extra money. Their initial cost to obtain the information for the job was \( \$ 650 \). Each envelope costs \( \$ 0.03 \) and they get paid \( \$ 0.08 \) per envelope stuffed. Let \( x \) represent the number of envelopes stuffed. (a) Express the cost \( C \) as a function of \( x \). (b) Express the revenue \( R \) as a function of \( x \). (c) Determine analytically the value of \( x \) for which revenue equals cost. (a) \( C(x)=\square \) ( \( C \) in dollars) (b) \( R(x)=\square \) (R in dollars) (c) Revenue equals cost when \( x=\square \)

will be cqual, if either \( b=0 \), or \( a^{3}+b^{2}+c^{3}-3 a b c-0 \). If \( a, b, c \) arc rational and \( a+b+c=0 \), show that the roots of \( (b+c-a) x^{2}+(c+a-b) x+ \) \( (a+b-c)=0 \) are rational.

(59.) \( a b-b^{2}, a^{2} b+b \) এর গসাগু কত?

\( 4 x^{2}+k x+5=0 \) has roots whose difference is \( \frac{1}{4} \)

4. Na natureza há bactérias que se multiplicam tão rapidamente que dobram de volume a cada minuto. Partindo-se de uma bactérias, sendo \( V(t) \) o volume de uma bactéria analisada após \( t \) minutos, e sendo \( V(t)=V_{0} \times 2^{t} \) a relação que fornece o volume da bactéria no instante t , onde \( V_{0} \) é o volume inicial da bactéria. Determine após quanto tempo, uma bactéria de volume inicial igual a \( 2 \mu \mathrm{~g} \) chega a \( 2048 \mu \mathrm{~g} \).

3. Uis tiene el triple de dinero de maria menos \( \$ 1,0000 \) si entre ambos tienen \( \$ 110,000 \) ¿Cuanto dinero tiene en tatal maria?