Answer
$\text{exponential decay;}$
$y$-intercept = $0.6$
Work Step by Step
Recall:
The exponential function $y=c \cdot b^x$ involves exponential:
(i) growth when $b\gt 1$
(ii) decay when $0 \lt b \lt 1$
The given exponential function has $b=\frac{1}{10}$, which is between $0$ and $1$, therefore it involves exponential decay.
The $y$-intercept of a function can be found by setting $x=0$ then solving for $y$.
Set $x=0$ then solve for $y$ to obtain:
\begin{align*}
y&=0.6\left(\frac{1}{10}\right)^x\\
y&=0.6\left(\frac{1}{10}\right)^0\\
y&=0.6(1)\\
y&=0.6
\end{align*}
Thus, the $y$-intercept is $0.6$.