SMS RO,50 per SMS 2.1. What does SMS stand for? 2.2. Calculate the amount that Mpho will pay to wnte 10 SMS's 10 triends. 2.3. Determine the balance on Mpho's coll phone if sho buys airtime for R3O and (3) makes an MTN call for 43 minutes.

3.20. Para \( n \in \mathbb{Z}^{+} \)se define \( f(n) \) como el número de enteros positivos \( <n \) que sc primos relativos con \( n \), por ejemplo \[ \begin{aligned} f(1)=1, \\ f(2)=1, \\ f(3)=2, \\ f(4)=2 .\end{aligned} \] 3.20.1. Calcular \( f(10), f(13), f(18), f(24) \). 3.20.2. Para \( n=12,18,19,25 \) calcule 3.20.3. Infiera una fórmula para \[ \sum_{d \mid n} f(d) . \] donde \( n \in \mathbb{Z}^{+} \). \( \sum_{d \mid n} f(d) \),

1. Bakit sinasabing mahirap bumuo ng pasya? 2. Paano nakakaapekto sa ibang tao ang pagbuo ng pasya? 3. Nakabuo ka na ba ng mahalagang pasya? Tungkol saan ito? Nahirapan ka bang magpasya? Bakit o bakit hindi? 4. Ano ang nararamdaman mo pagkatapos mong magpasya? 5. Paano nararating ang mabuting pasya?

Decide whether the following statement is true or false. The graph of \( y=-f(x) \) is the reflection about the \( x \)-axis of the graph of \( y=f(x) \). Choose the correct answer below. False True

Westside' and 'Westcoast' hand signs [GENERAL / AMERICA].

3.20. Para \( n \in \mathbb{Z}^{+} \)se define \( f(n) \) como el número de enteros positivos \( <n \) que son primos relativos con \( n \), por ejemplo \[ \begin{aligned} f(1)=1, \\ f(2)=1, \\ f(3)=2, \\ f(4)=2\end{aligned} \] 3.20.1. Calcular \( f(10), f(13), f(18), f(24) \) \( \begin{array}{l}\text { 3.20.2. Para } n=12,18,19,25 \text { calcule } \\ \text { 3.20.3. Infiera una fórmula para } \\ \qquad\end{array} \)