The phrase "a challenging task and" is correct and usable in written English.
It can be used when describing a task that is difficult and when you want to add more information or context about it.
Example: "Completing the project on time is a challenging task and requires careful planning and teamwork."
Alternatives: "a difficult task and" or "a demanding task and".
In fact, its environmental friendly management and disposal is a challenging task and requires careful consideration.
Dealing with such data is a challenging task and requires robust and accurate segmentation methods.
The construction of basis functions for such elements is a challenging task and may require extensive geometrical analysis.
Spray drying of pharmaceutical compounds with sticky properties is a challenging task and may require substantial time and resources.
It's a challenging task and one that is hard to fund but if successful, it can create new markets and enable sustainable enterprises to thrive.
The extension of single-site approaches to multiple sites is a challenging task, and has led to a large variety of different model philosophies for multi-site models.
Studying how individuals construct their preferences among competing life goals and build intended family trajectories is a challenging task and pertains to an under-investigated area of research.
However, the large number of different modeling techniques and complexity in the patterns make finding the optimum texture a challenging task and have led to contrary conclusions.
Understating the adaptation mechanism of enzymes to pH extremes and discriminating them is a challenging task and would help to design stable enzymes.
Generation of steep waves (H/λ>0.03) in a NSE-based NWT is a challenging task and is seldom attempted in near-shallow water (kh<1.0).
Integrated design and control of PSA system, incorporating its highly nonlinear and dynamic nature remains a challenging task and is the focus of this study.
